It is estimated that the average American residence uses in the range of 100,000 gallons of water annually and that more water is used to flush toilets than showering or any other individual activity (Reference: Indoor Water Use in the United States, US EPA, June 2008, EPA-832-F-06-004). Grey water is defined as lightly used or unprocessed water which can be re-applied, in this case, to the flushing of toilets. Currently, almost all grey water is disposed of right after leaving the source fixture (e.g. a wash basin) or appliance (e.g. a washing machine). Numerous grey water toilet systems have been proposed in order to conserve water.
One type of system serves an entire building and utilizes a common reservoir where grey water is collected from the sinks, showers, bath tubs, washing machines, rain collection points, appliances etc. The stored grey water is then utilized by grey water applications such as toilets. This type of system requires extensive design and integration and is costly to retrofit into existing buildings. Examples of these systems include U.S. Pat. No. 4,115,879, 1978 Toms; U.S. Pat. No. 4,197,597, 1980 Toms; U.S. Pat. No. 4,162,218, 1979 McCormick; U.S. Pat. No. 5,345,625, 1994 Diemand; U.S. Pat. No. 5,452,956, 1995 Gilliam; U.S. Pat. No. 5,496,468, 1996 Cormier; U.S. Pat. No. 5,498,330, 1996 Delle Cave; U.S. Pat. No. 5,573,677, 1996 Dembrosky; U.S. Pat. No. 5,845,346, 1998 Johnson; U.S. Pat. No. 6,328,882, 2001 Rosenblatt; U.S. Pat. No. 6,702,942, 2004 Nield; U.S. Pat. No. 6,796,250, 2004 Greene; U.S. Pat. No. 6,889,395, 2005 Hodges; 6904926, 2005 Aylward et al.; 7121292, 2006 Aylward et al.; 8974663, 2015 Aylward et al.; 7913331, 2011 Hartman; U.S. Pat. No. 8,696,897, 2014 Marugame; U.S. Pat. No. 5,084,920, 1992 Kimball.
Less expansive grey water toilet systems include connected sink/toilet combinations, FIG. 1 (examples include U.S. Pat. No. 4,358,864, 1982 Medrano; U.S. Pat. No. 6,276,005, 2001 Sanders et al.; 6802090, 2004 Martin; and U.S. Pat. No. 8,931,122, 2015 Cerce) as well as integrated sink/toilet fixtures, FIG. 2, FIG. 3 (examples include U.S. Pat. No. 5,813,047, 1998 Teichroeb and U.S. Pat. No. 9,057,186, 2015 Augustine). However, even these simpler grey water toilet systems require a significant investment to install into existing bathrooms due to the need for remodeling the bathroom area. Often, replacement or repositioning of the existing fixtures is necessary. In addition, some of these systems require electrical access to power the pump 11 used to pressurize or move the grey water from a storage reservoir 12 to the toilet 10 (examples include U.S. Pat. No. 5,201,082, 1993 Rockwell; U.S. Pat. No. 5,317,766, 1994 McDonald et al.; 5937455, 1999 Donati; and U.S. Pat. No. 0,059,755, 2014 Garrels et al.). The various costs associated with the installation of a grey water toilet such as remodeling, outage time, and inconvenience, are deterrents to the adoption of these systems.
Foot operated devices have been applied for different individual toilet functions in the past. Foot pedals have been used to trigger the flush operation of toilets for many years. Examples include U.S. Pat. No. 1,585,557, 1924 Miller; U.S. Pat. No. 1,864,827, 1931 Jenkins et al.; 2467019, 1944 Farson; U.S. Pat. No. 3,594,828, 1971 Seek; U.S. Pat. No. 3,594,829, 1971 Seek; U.S. Pat. No. 3,883,904, 1975 Wittman; U.S. Pat. No. 5,142,708 1992 Johnson et al.; U.S. Pat. No. 8,286,273 B1, 2012 Toomer; and D6492335, 2011 Du, as well as Chinese patents: CN202370063U, 2012 and CN203222872U, 2013. These devices attach to the existing flush mechanisms of toilets and apply a small amount of energy from a user's foot action to trigger a flush event, providing more hygienic touch free flushing. Foot powered pumps have also been proposed to provide flush water for portable toilets. An example is U.S. Pat. No. 5,398,465, 1995 Tagg. Foot powered pumps and water transfer mechanisms for flushing toilets have been proposed by several Chinese patents: CN2166167Y, 1994; CN2355010Y, 1999; CN2407051Y, 2000; CN2496938Y, 2002; CN2639383Y, 2004; CN2742053Y, 2005; and CN103726543A, 2014. However, these foot powered water transfer devices are not designed to integrate with existing toilets and require custom installation or remodeling. Some are standalone components and do not offer a complete solution. For example, many of these designs require installation of a custom toilet versus integrating with an existing toilet. A practical grey water toilet retrofit system should handle all the functions related to flushing a toilet with simple input from the user. These functions include: triggering the flush mechanism, resupplying the toilet tank with grey water and handling situations when there is either too much or too little grey water. The use of grey water in toilets has not been commercially viable or widely available in part due to the high cost to retrofit existing toilets with a practical system. The goal of this invention is to overcome these obstacles.